AlexK987 <alex.cue.987@xxxxxxxxx> writes: > I believe that tables' clustering factors are stored in pg_stats.correlation. Dunno what you mean by "clustering factor", but pg_stats.correlation stores the correlation coefficient between the sequence of the column's data values and the sequence of their physical order. Correlation coefficient is defined in the usual way: http://en.wikipedia.org/wiki/Pearson_product-moment_correlation_coefficient so it ranges between +1 in your example (perfect ordering) and -1 (perfect descending order). regards, tom lane -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general